I am not a fan of the sharp nickel corners over the positive terminals. The balance cables should be run over fishpaper, not on the bare cells. Also if the balance cables cross, there should be fishpaper in between them. Most if not all spot welds are too hot, and I can see that you blew through the nickel a few times. I am a little worried about nickel on nickel connections usually, as they are hard to actually weld on robustly. The solder joints look like they will hold, but they don’t look clean. Probably low quality solder. But for an ebike, these issues are probably all passable, even though not ideal. I’ve seen worse in Chinese production ones from the factory… If you were to build a pack for an esk8 or escooter, then you would have to keep all these extra things in mind. I personally build all my ebike packs to meet the esk8 standards.
However:
You absolutely need fishpaper under the folded nickel here! That’s really important
If you want some inspiration you can check out my thread. There are a couple ebike battery packs in there.